Compound semiconductor material is often used in the manufacture of electronic components. The most common compound semiconductor materials consist of substances of the III and V groups of the Periodic Table, in particular, gallium arsenide or indium phosphide. Multiple compounds, for example, GaAlAs, GainAs or GainAsP are also often used. In particular, optoelectronic components, semiconductor lasers, components with Schottky junctions and integrated semiconductor circuits are manufactured on the basis of such semiconductor materials. The starting point in the manufacture of the aforementioned components is a base body which may be manufactured in various ways, for example, by zone melting, by the horizontal Bridgman process or by the LEC (liquid encapsulated Czochralski) process. One or several semiconductor layers is/are deposited--preferably by epitaxial deposition--on this base body.
The dislocation concentration in the semiconductor base body is decisive to the quality of the epitaxial layers which may be deposited by liquid-phase epitaxy or by vapor-phase epitaxy. To each further epitaxial layer growing, the height of the dislocation concentration in the epitaxial layers located thereunder is of essential importance. In the pertinent literature, dislocation concentrations of between 10.sup.4 -10.sup.5 /cm.sup.2 are indicated as relatively low.
For the manufacture of high quality components, the aforementioned dislocation concentration values are, however, much too large. To manufacture field-effect transistors, for example, certain structures are built into the base bodies with the aforementioned dislocation concentrations by, implantations of impurities. The electric characteristic values of these field-effect transistors are considerably impaired by the aforementioned high dislocation concentration in the base body.
The dislocations which continue in the epitaxial layers also cause serious disturbances in the build-up of multilayer structures with heterojunctions. In these components, layers which do not exhibit exactly the same lattice spacing with respect to each other and to the semiconductor base body are deposited on a base body. The base body often consists of a dual compound semiconductor such as gallium arsenide or indium phosphide, on which layers of ternary or quaternary material such as, for example, GaAlAs or GaInAsP are deposited. Since the lattice spacings of the materials of the various layers do not exactly coincide with one another, but a monocrystalline growth is required, it is clear that a high dislocation concentration in the base body or in the base layer provided for the deposition has a very disturbing effect. A number of recombination centers which result in a very strong decrease of the carrier lifetime then occur in the aforementioned epitaxial layers. The characteristic lines of the junctions between various layers and between the base body and the epitaxial layer arranged thereon is substantially impaired by the high dislocation concentration in comparison to the ideal values. In light emitters, a high dislocation concentration causes a bad luminescence efficiency, which results in a low efficiency of light emitting diodes and laser arrangements.